Thursday, February 26, 2009

In 1982, the United States Congress passed a law requiring the Department of Energy to find a suitable site to construct a disposal facility for the radioactive spent fuel from commercial nuclear reactors. In 2005, 52,000 tonnes of spent fuel was being held at nuclear power and military facilities in the US. And it is estimated that by 2015, the nation's nuclear power facilities will be storing over 75,000 metric tons of spent fuel on site. There are laws preventing the expansion of nuclear power within several States in the US until a final storage solution is found for the radioactive spent fuel accumulating at current commercial nuclear reactor sites. And to fund such a permanent storage facility, nuclear utilities have paid nearly $30 billion in fees and interest to a Federal “nuclear waste fund”.

Nuclear Energy Institute map of stored radioactive waste from the commercial and military nuclear industry

Eventually, Yucca Mountain became the Department of Energy's solution to the nations nuclear waste problem. Over 2 billion dollars has been spent studying the Yucca Mountain area in Nevada with an additional 5 to 6 billion dollars to finish the facility by 2010. But there has been strong political and environmental opposition to storing spent fuel at the Yucca Mountain facility. Harry Reid, Senator from Nevada and the current leader of the US Senate, strongly opposes Yucca Mountain as a repository for the nation's nuclear waste material. And President Barack Obama ran in opposition to utilizing the Yucca Mountain facility for radwaste deposition during his campaign for president.

So it now seems unlikely that the Yucca Mountain facility in Nevada will be utilized for the deposition of the nation's spent fuel. And the Nuclear Energy Institute has reportedly recently advanced the idea that President Barack Obama convene a blue ribbon nuclear waste commission to find an alternative to burying radioactive power plant fuel at Yucca Mountain.

Despite that fact that there are tens of thousands of tonnes of spent fuel now residing at US commercial nuclear power plants, it should be noted that only 3 or 4% of that spent fuel is actually radioactive waste. After enriched uranium is utilized in a nuclear reactor for fuel, 96% of the remaining mass is in the form of the original fertile uranium 238 with a residual component of fissile uranium 235 composing about 0.83% of the total uranium content. This percentage of uranium 235 is down from its original 3% as fuel, but still higher than the 0.71% natural concentration of uranium. An additional 1% of the spent fuel is in the form of fissile plutonium 239. And the rest is in the form of fission products and minor actinides. Since the uranium and plutonium can be recycled and utilized for fuel, only 3% or 4% of spent fuel can actually be considered as radioactive waste material.

So instead of the Federal government using the 30 billion dollars given to them by the utilities to simply throw away the spent fuel, I propose that the Federal government use that money along with additional Federal investment funds to dispose of 96% of the spent fuel by recycling the fissile material and converting it into clean energy.

I propose that a Federal Nuplex Corporation should be established in order to fund the construction of Federal Nuplexes in every State that is currently storing spent fuel at their nuclear power facilities and for every State willing to take in spent fuel from other states.

I envision Federal Nuplex facilities as consisting of:

1. Temporary storage areas for spent fuel cask recently imported from nuclear power facilities within the state

2. On site spent fuel reprocessing facilities to extract uranium and plutonium fuel on site utilization

3. On site uranium enrichment facilities to fabricate uranium fuel for on site reactors

4.8 to 40 on site nuclear reactors capable of using the recycled uranium and plutonium fuel for base-load electricity production

5. Long term storage cask for housing the reprocessed radioactive spent fuel fission products and minor actinides from nuclear reactors

6. Adjacent site synfuel production facilities for the production of carbon neutral gasoline, methanol, diesel fuel, jet fuel, dimethyl ether, hydrogen, oxygen, and ammonia for the transportation and industrial chemical industry

7. Off site (up to 80 kilometers) methanol-oxygen cogeneration and trigeneration power facilities for the production of peak-load electricity

8. On site storage facilities for radioactive waste from hospitals and radioactive research facilities

A State's spent fuel could be transported by rail to the Federal Nuplex facility located within the state. The residual nuclear waste produced after reprocessing would be stored on site for a few hundred years until either transmutation or final out of state deposition. On site reactors could also be decommissioned on site after energy production from a Nuplex has finally ceased. The safest and most economical way to decommission a reactor facility would be to allow the irradiated components of the facility to decay over the coarse of 100 to 200 years. So if you assume that several reactors would be gradually added to a nuplex over the course of the next 30 or 40 years and that these reactors will continue to operate for at least 60 to 80 years then Nuplex facilities would probably not be completely decommissioned and removed from its site until at least 300 years from now, or not until the 24th century. So any residual radioactive waste could remain on site at secured Nuplex facilities for a few hundred years until the material is eventually transmuted into shorter lived elements or permanently deposited in deep sea beds or in some extraterrestrial environment in the 24th century.

Spent fuel cask being transported by rail

A typical Nuplex could contain perhaps four AP 1000 light water reactors plus four ACR 1000 heavy water reactors. The recycled plutonium and uranium could be used inside of a thorium blanket inside of an ACR reactor to reduce plutonium production while producing more uranium 233. A Heavy Water Reactor utilizing thorium could in theory have an 80% conversion ratio or above almost to the point of being self-sustaining. The AP 1000 Light Water Reactor could use the recycled and enriched uranium to produce power or the plutonium as MOX, or the plutonium in a mixture of a thorium-uranium blanket

Federal Nuplexes would contain between 8 to 40 reactors. Concentrating so many reactors at one site could substantially reduce the capital cost of the power facility due to economies of mass production and large concentrated facilities could also reduced labor and security cost. Each Nuplex would also produce thousands of permanent jobs. But because of the heat island effect, it may be necessary to limit the number of nuclear reactors at a site to ten or less. However, if waste it is dissipated by locating several cooling ponds and dry cooling towers in all directions, several kilometers off site, then this effect could be mitigated. Alternatively, the heat island effect could be mitigated by utilizing the waste heat for seawater desalinization, greenhouse and hydroponic agriculture, or aquaculture.

Because the Federal government would be reprocessing domestic spent fuel on Federally protected facilities, there should be no danger of nuclear proliferation. Additionally, the export of Nuplex produced synfuels to other countries for electric power production, transportation, and industrial chemicals would enable foreign nations to benefit from the production of nuclear energy without the need for nuclear facilities or nuclear material.

Federal Nuplexes would eliminate the need for long term storage of spent fuel at commercial nuclear reactors sites. They would also substantially reduce the volume of spent fuel produced by the commercial nuclear industry while also substantially increasing the amount of nuclear energy produce for base-load electricity and synfuel production. As the Secretary of Energy Steven Chu has already noted, nuclear power plants already produce 100 times less radioactive material than coal power facilities. Nuplexes could furter reduce radwaste production by more than 1000 times relative coal power production. Finally, Federal Nuplexes would allow regional utilities to increase the number of reactors on existing sites without the long term trouble of managing and storing spent fuel.

Thursday, February 19, 2009

In January of 2007, petroleum prices dipped below $60 per barrel. But by March of 2008, oil prices had begun to peak above the $100 per barrel mark. And by July of 2008, oil prices had risen above $140 per barrel! But as the global economy began to decline, oil prices had again fallen below $100 per barrel by October of 2008 and as of late February 2009, the price of oil now stands at below $40 per barrel. Average gasoline prices in the US have also declined from a record $4.11 per gallon in July of 2008 to below $2.00 a gallon as of February of 2009.

Advocates of alternative fuels have bemoaned the current low price of oil as a hindrance towards weaning America off foreign oil and the petroleum fuel economy. However, I view low oil prices as a great economic opportunity to gradually introduce the higher priced carbon neutral synthetic fuels into the American hydrocarbon fuel economy as a component of our total liquid transportation fuel economy.

In 2006, the USA consumed more than 20 million barrels of oil per day while producing only 8 million barrels of oil daily while importing more than 12 million barrels of oil per day.

Thanks to America's importation of huge amounts of foreign oil, several hundred billion dollars of America's national wealth is being exported to foreign nations on an annual basis. And as we continue to use petroleum products for fuel and industrial chemicals, we continue to add substantially more excess CO2 to the atmosphere which is heating up our planet, accelerating the melting of the ice caps, and raising global sea levels.

With oil prices so low, some have argued that this is a perfect time to increase taxes on gasoline in order to fund alternative fuels and to provide incentives for drivers to continue to conserve fuel. However, some believe that raising taxes during a global economic recession (or depression) is a bad idea. However, I believe that mandating the a certain percentage of all gasoline, diesel fuel, and aviation fuel be composed of carbon neutral synfuels is a better alternative than raising taxes and would be a far more effective means for moving America away from the petroleum fuel economy.

If the Federal government mandated that just 5% of all gasoline, diesel fuel, jet fuel and industrial hydrocarbon chemicals in the US be composed of carbon neutral hydrocarbon fuels and industrial chemicals by the year 2015 and 10% by the year 2020 then a huge new carbon neutral synfuel industry could be created in the United States that could possibly completely replace the need for foreign and domestic petroleum in the US by the year 2050 and possibly even sooner.

Sources for these carbon neutral hydrocarbon fuels and industrial chemicals could come from:

All of these sources of hydrocarbons could produce carbon neutral gasoline, diesel fuel, aviation fuel, methanol, methane, in addition to industrial chemicals such as hydrogen and ammonia. However, there is only enough easily available urban and rural biowaste to supply about 6% of America's total petroleum needs. So any substantial environmentally friendly increase in carbon neutral synfuels beyond that level would probably require a substantial increase in synfuels from the synthesis of hydrogen and carbon dioxide via clean nuclear, hydroelectric, wind, and solar electricity resources.

The current cost of these synthetic fuels and industrial chemicals would be generally higher than similar fuels derived from petroleum. However, these relatively more expensive synfuels would only be a small percentage of the total fuel cost since they would initially only be a small percentage of the total fuel content.

For instance, the GreenFreedom advocates argue that current nuclear reactors combined with electrolysis and CO2 extraction technologies could produce 18,000 barrels of oil equivalent gasoline per day for a 1000 MWe nuclear reactor at an estimated operating cost of just $1.40 per gallon. However, this doesn't include the capital cost of the nuclear reactor and the associated synthetic fuel facility and a reasonable profit margin which they conclude would raise the price of nuclear produced gasoline to $4.60 per gallon. Of course the capital cost of nuclear reactors and synfuel facilities would probably fall dramatically due to economies of mass production since it would require the construction of at least 700 new 1GWe reactors to produce enough gasoline for US consumption, or perhaps only half as many reactors (350) if all gasoline vehicles in the US are PHEV (plug-in-electric vehicles) in the 2020s.

So if all gasoline in the US were required to consist of at least 10% carbon neutral gasoline then $2.00 per gallon gasoline from petroleum combined with $4.60 per gallon of carbon neutral gasoline would cost $2.26 per gallon. Of course, if you're driving one of those future plug-in-hybrid vehicles (PHEV) in the 2020s then the cost of electricity could cost you as little as $0.75 per gallon. So your equivalent cost per gallon using 50% electricity, 45% gasoline from petroleum and 5% carbon neutral synthetic gasoline would be approximately $1.88 per gallon. Using nuclear derived carbon neutral gasoline alone in a PHEV would cost you approximately $3.05 per gallon which is still far below the peak cost of $4.11 per gallon US consumers payed for gasoline in July of 2008.

Sunday, February 8, 2009

Robert Duncan has just written one of the best articles that I've read on the TVA coal disaster situation that began last December after a deluge of coal-ash slurry (waste originating from the Kington Coal electric power facility) inundated a valley in eastern Tennessee destroying homes and polluting the Emory River.

The two power plants Duncan refers to are the Kingston "Clean coal" power facility and the Watts Bar nuclear facility, comparing the clean nuclear facility to the dirty Kingston coal facility. Its a great article!

The Pro-Nuclear Democrats blog also discussed the TVA coal disaster in January which features a video of the disaster. Coal is simply bad news.

But even more provocatively, I believe that most of those future automobiles could also be fully automated. In other words, our cars could become our first popular domestic robot servants, our chauffeurs! Could you imagine using your cell phone to order your car to pick you up at work and then driving you home while you take a short nap in the back seat (You had a long day!). And once you arrived at your house, you might hear an automated voice saying "Dave, we're home. We're home Dave."

Monday, February 2, 2009

In 2002, Nature magazine announced to the world that French paleontologist, Michel Brunet, and his colleagues had discovered the fossil cranium of the earliest human ancestor. The fossil remains of a skull and jaw had been found on July, 19, 2001, in the Djurab desert in the Central African country of Chad by a Chadian student (Ahounta Djimdoumalbaye) working with the Brunet team. The president of Chad named it Toumai (hope of life), a nickname often given to Chadian children born in the dry season. But Brunet's team named it Sahelanthropus tchadensis after the African region that borders the African savanna and the Sahara desert and after the nation where it was found.

Sahelanthropus was originally dated at between 6 to 7 million years old. But the most recent estimates have determined that the fossil skull and the other hominins remains were between 6.8 and 7.2 million years old. This would make Sahelanthropus older than later fossil hominins Ardipithecus and Australopithecus and, therefore, the oldest fossil human ancestors ever found in Africa.

Some researchers, however, have questioned the hominin (humans, human ancestors, and close non-ape human relatives) status of Sahelanthropus, arguing that the fossil hominoid may actually be more closely related to the gorilla or the chimpanzee rather than to humans and their non-ape human relatives such as Australopithecus.

Sahelanthropus tchadensis possessed several cranio-dental (skull and teeth) characteristics that are also found in other extant and extinct hominoids. These cranio-dental characteristics include:

At least some of these 17 morphological characteristics can be found amongst a group of extant and extinct hominoids that include Homo (humans and their immediate ancestors), Australopithecus (ancient gracile and robust human relatives), Pan (chimpanzee and bonobo), gorilla, Pongo (orangutan) and Hylobates (gibbon). Of these cranio-dental characteristics, the gibbon has the fewest sahelanthopine characteristics, possessing only three . The orangutan also has few Sahelanthropus features, possessing only 4 similar cranio-dental characteristics with the Toumai fossil. The chimpanzee and gorilla each share only 5 cranio-dental similarities with with Sahelanthropus. So the Asian apes (gibbon and orangutan) have an 18 to 24 % cranio-dental similarity to Sahelanthropus respectively while the gorilla and chimpanzee have only a 29% cranio-dental similarity with the Toumai fossil.

Amongst the hominins (Homo and Australopithecus), Homo has 10 cranio-dental similarities with Sahelanthropus, a 59% cranio-dental similarity. The more ancient australopithecines, however, have even more morphological similarities with Sahelanthropus possessing 14 cranio-dental similarities, an 82% similarity. So the cranio-dental evidence clearly shows that Sahelanthropus was morphologically much more similar to humans and australopithecines than it was to African and Asian apes.

Evidence that the angle of the foramen magnum (the large opening at the base of the skull forming the passage from the cranial cavity to the spinal canal) relative to the orbital plane of the skull in Sahelanthropus is similar to that found in bipedal humans and bipedal hominins such as Australopithecus africanus and Australopithecus afarensis adds further evidence that the 6.8 to 7.2 million year old Sahelanthropus tchadensis was probably the earliest African ancestor of the human species.

"The knowledge that we have now is but a fraction of the knowledge we must get, whether for peaceful use or for national defense. We must depend on intensive research to acquire the further knowledge we need ... These are truths that every scientist knows. They are truths that the American people need to understand." (Harry S. Truman 1948).